000
FXUS63 KDLH 301743
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1243 PM CDT THU JUL 30 2015
.UPDATE...
ISSUED AT 1235 PM CDT THU JUL 30 2015
UPDATE FOR 18Z AVIATION DISCUSSION BELOW...
UPDATE ISSUED AT 1101 AM CDT THU JUL 30 2015
MADE SOME ADJUSTMENTS TO THUNDERSTORM MENTION AS DRIER AIR IS
WINNING OUT OVER THE MORE ROBUST APPROACH OF EARLIER.
UPDATE ISSUED AT 902 AM CDT THU JUL 30 2015
BEEFED UP THE MENTION OF SHOWERS AND THUNDERSTORMS OVER THE
NORTHERN THIRD OF THE AREA...MAINLY NORTH OF U.S. HIGHWAY 2...AS
WELL AS IN NW WI NEAR LAKE SUPERIOR. LATEST SHORT TERM HIRES
MODELS ARE POINTING TO THESE AREAS HAVING THE BETTER OPPORTUNITY
TO SEE SOME ACTIVITY TODAY. MADE SOME OTHER MINOR ADJUSTMENTS AS
WELL.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 324 AM CDT THU JUL 30 2015
CONCERN FOR SHORT TERM IS CHANCES FOR PRECIP THIS AFTERNOON AND
FRI AFTERNOON
CURRENT SURFACE ANALYSIS INDICATES CLEAR SKIES ACROSS THE FORECAST
AREA WITH TEMPS IN THE 60S. WINDS ARE GENERALLY 8-12 MPH AND HAVE
DECREASED FROM WEDNESDAY. THE AREA OF LOW PRESSURE THAT BROUGHT
THE HIGH WINDS YESTERDAY IS WEAKENING AND PULLING OFF TO THE
NORTHEAST DECREASING WIND SPEEDS TODAY. HOWEVER...THE CYCLONIC
FLOW AROUND THE LOW WILL KEEP PUSH COOLER AIR ALOFT THROUGH
FRIDAY. INSTABILITY WILL DEVELOP BY THIS AFTERNOON DUE TO SOLAR
HEATING ESPECIALLY NORTH OF HIGHWAY 2 IN MN. SHOWERS AND
POSSIBILITY OF A THUNDERSTORM COULD DEVELOP AFTER 18Z TODAY AND
CONTINUE THROUGH 23Z AFTER THE HEATING DECREASES. THE
PRECIPITATION WILL BE SCATTERED ACROSS THE AFFECTED AREAS.
SKIES WILL BE CLEAR TO PARTLY CLOUDY TONIGHT WITH LOWS IN THE 50S.
CYCLONIC FLOW WILL BE AFFECTING THE BORDERLAND ON FRIDAY WHICH
WILL CAUSE ANOTHER POSSIBILITY OF SHOWERS TO DEVELOP ACROSS THOSE
AREAS IN THE AFTERNOON.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 324 AM CDT THU JUL 30 2015
THE QUASI STATIONARY LOW OVER HUDSON BAY WILL KEEP THE FORECAST AREA
IN A REGION OF UNSTABLE CYCLONIC/NORTHWEST FLOW WITH FALLING MID
LEVEL TEMPERATURES THROUGH THE EXTENDED PERIOD. LATEST ECM/GFS ARE
EVEN SUGGESTING THAT AN AIR MASS WITH H85 TEMPS IN THE SINGLE DIGITS
SKIRTS PAST THE BORDERLAND/ARROWHEAD ZONES BY EARLY NEXT WEEK. THE
COOLING AIR ALOFT WILL PRODUCE STEEP AFTERNOON LAPSE RATES AND DEEP
MIXING...RESULTING IN GUSTY NW WINDS AND LOW RH VALUES FOR THE
WEEKEND.
OVERALL TEMPERATURES WILL BE BELOW NORMAL THROUGH NEXT WEEK...WITH
HIGHS HOLDING IN THE 60S AND 70S. LONG RANGE MODELS SUGGEST THE LOW
SWINGS SEVERAL FAST MOVING SMALL WAVES ACROSS THE WESTERN GREAT
LAKES REGION....RESULTING IN PERIODIC SMALL POPS AND INCREASING
CLOUDS THROUGHOUT THE EXTENDED. HOWEVER...THE COVERAGE OF ANY
SHOWERS/ISOLATED STORMS WILL BE MINIMAL AND THE TIMING OF THESE
WAVES ARE DIFFICULT TO PIN DOWN THIS FAR OUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1243 PM CDT THU JUL 30 2015
VFR CONDITIONS WILL CONTINUE THROUGH FORECAST PERIOD. MODEST COLD
AIR ADVECTION IN THE MID LEVELS SUPPORTS A CHANCE OF ISOLATED/
SCATTERED SHOWERS AT HYR. INSTABILITY IS STRONGER OVER NE
MINNESOTA...SO THINK HIGHER CHANCE OF THUNDER VS ORDINARY SHOWERS
AT INL AND HIB. CONFIDENCE IN COVERAGE AND TIMING IS STILL
UNCERTAIN...SO HANDLING AS VC AT ALL SITES FOR NOW. WINDS WILL BE
GUSTY THIS AFTERNOON AT ALL SITES AS DAYTIME HEATING ALLOWS
STRONGER FLOW ALOFT TO MIX DOWN TO THE SURFACE. PRECIP AND GUSTY
WINDS WILL DIMINISH EARLY THIS EVENING. ALSO MONITORING LLWS
POTENTIAL AT MN SITES LATE THIS EVENING AND EARLY FRIDAY MORNING.
THIS MORNINGS GUIDANCE KEEPS ALL TERMINALS BELOW THRESHOLD FOR
LLWS...BUT HIB/INL/BRD ALL APPROACH 30 KT VECTOR DIFFERENCES
BETWEEN SFC AND 2 KFT AGL BETWEEN 31.02Z AND 31.09Z. WINDS BECOME
GUSTY AGAIN FRIDAY MORNING AS HIGHER WINDS ALOFT MIX DOWN.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 80 60 78 58 / 0 10 0 10
INL 78 53 76 50 / 0 20 20 10
BRD 83 59 80 54 / 0 0 0 10
HYR 80 56 77 53 / 0 10 0 10
ASX 80 59 78 56 / 0 20 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...STEWART
LONG TERM...GRANING
AVIATION...HUYCK